A conventional scroll refrigeration compressor includes:                a closed container,        a scroll compression unit disposed in the closed container and including:                    a fixed scroll including a fixed base plate and a fixed spiral wrap,            an orbiting scroll including an orbiting base plate and an orbiting spiral wrap, the fixed spiral wrap and the orbiting spiral wrap forming a plurality of compression chambers,                        a drive shaft configured to drive the orbiting scroll in an orbital movement,        a driving unit coupled to the drive shaft and configured to drive in rotation the drive shaft about a rotation axis,        a support frame on which the orbiting base plate is slidably mounted, the support frame including a bearing configured to guide in rotation a guided portion of the drive shaft,        an Oldham coupling configured to prevent rotation of the orbiting scroll with respect to the fixed scroll and the support frame, the Oldham coupling including a pair of first engaging elements respectively slidably engaged with a pair of complementary engaging elements provided on the support frame, and a pair of second engaging elements respectively slidably engaged with a pair of complementary engaging elements provided on the fixed scroll,        a refrigerant suction part suitable for supplying the scroll compression unit with refrigerant to be compressed, and        an oil sump.        
Typically, the Oldham coupling is disposed inside the refrigerant flow path. Thus, the engaging elements of the Oldham coupling can be lubricated by the oil droplets contained in the refrigerant.
However, such a lubrication of the engaging elements of the Oldham coupling by means of the refrigerant may be insufficient, notably when the refrigerant has a low oil content, particularly when the refrigerant is a propane refrigerant such as R290 refrigerant, or when the Oldham coupling is disposed outside the refrigerant flow path, which may harm the efficiency and the reliability of the scroll compression unit, and thus of the scroll compressor.